And hats off to faculty advisors Alyson Brooks and Matt Buckley. These findings could open the door to novel graphene-based electronic building blocks. Their article is published in Nature Nanotechnology advanced online publication.
A nonlinear pulse width modulation-controlled single-phase boost mode photovoltaic grid-connected inverter with limited storage inductance current is proposed in this paper.
The circuit topology, control strategy, steady-state principle characteristic, and design criterion for the key circuit parameters of this kind of inverter are investigated in depth, and important conclusions are obtained. The active control of the energy storage inductance current and the balance of the voltage step-up ratio are realized by adding a bypass switch connected in parallel with the energy storage inductance and using two kinds of switching pattern namely boost pattern and freewheeling pattern.
The common-mode leakage current should be carefully considered when designing a transformer-less photovoltaic PV inverter since the leakage current can cause the output current distortion and increase the operational risk.
The unipolar sinusoidal pulse width modulation of the traditional H-bridge inverter can produce the superior output performance but will cause a high-frequency fluctuated common-mode voltage and consequently the nonnegligible leakage current. To attenuate the fluctuation phenomena of common-mode voltage, few neutral-point-clamped NPC circuits have been designed to clamp the neutral-point voltage and maintain the common-mode voltage constant.
This paper analyzes the equivalent common-mode circuit of single-phase inverters and proposes a generalized design principle of multiterminal NPC circuits, whose unidirectional and bidirectional variations are fully analyzed.
Also, the operational losses and component counts are compared between the proposed topologies and the traditional NPC inverters. The experimental results verified the theoretical findings.
Multilevel inverters are one of the preferred solutions for medium-voltage and high-power applications and have found successful industrial applications.
Five-level active neutral point clamped inverter 5L-ANPC is one of the most popular topologies among five-level inverters. The flying-capacitor capacitance is designed under both active and reactive power conditions. The analysis shows the proposed topology is suitable for photovoltaic grid-connected applications.
A 1 KVA single-phase experimental prototype is built to verify the validity and flexibility of the proposed topology and modulation method.
This paper proposes a circuit topology of a single-stage three-phase current-source photovoltaic PV grid-connected inverter with high voltage transmission ratio VTR.
The improved zone SPWM control strategy consists of two control loops, namely, the outer loop of input dc voltage of PV cells with the maximum power point tracking and the inner loop of the energy storage inductor current.
Nonetheless, it has small energy storage inductor and output CL filter, low output current total harmonic distortion, and flexible voltage configuration of the PV cells.
This study provides an effective design method for single-stage three-phase inverting with high VTR. This paper presents an improved cascaded multilevel inverter CMLI based on a highly efficient and reliable configuration for the minimization of the leakage current.
Apart from a reduced switch count, the proposed scheme has additional features of low switching and conduction losses. The proposed topology with the given pulse width modulation PWM technique reduces the high-frequency voltage transitions in the terminal and common-mode voltages.
Avoiding high-frequency voltage transitions achieves the minimization of the leakage current and reduction in the size of electromagnetic interference filters. Complete details of the analysis of PV terminal and common-mode voltages of the proposed CMLI using switching function concept, simulations, and experimental results are presented in the paper.
In this paper, an improved transformer-less single-phase single-stage grid-tied flying inductor inverter is presented. The negative terminal of the PV panel is grounded in the proposed topology, which increases reliability and suppresses the leakage current.
The proposed topology has buck-boost capability without increasing the number of required components and has considerably high efficiency.
An improved control algorithm for proper operation of the proposed topology has been investigated. Furthermore, design of the converter components based on maximum power which the proposed converter can inject is done. Simulation of the proposed converter is done in Matlab Simulink in order to verify the designed values and experimental prototype is developed in the same situation as the Simulink and design procedure to reconfirm the results of Simulink and design results.
Finally, a comparison study has been investigated for better clarification of the advantages and disadvantages of the proposed converter. The paper presents a reactive power control technique for single-phase Photovoltaic PV inverters, especially unfolding inverters.
The proposed system retains the benefit of the unfolding inverters having low material cost and semiconductor losses, and tackles the drawback of the standard unfolding inverter not having capability of reactive power injection.
It is important to note that reactive power delivery is mandatory for PV inverters according to the recent announced regulations.
The concept is based on changing the shape of the grid current waveform but keeping the same zero crossing points as in the unity power factor condition. The current waveform is governed by real power and reactive power, at the price of an acceptable deformation.
The operating principles of the proposed technique and mathematical derivations of the grid current function are provided in the paper. Experimental results in a grid-tie inverter prototype have shown a good agreement with the derived theory, and they confirm the feasibility of using the proposed technique in grid-tie inverters.
For the safe operation of transformerless grid connected photovoltaic PV inverters, the issue of common mode CM leakage current needs to be addressed carefully. In this paper, a novel multilevel transformerless inverter topology is proposed, which completely eliminates CM leakage current by connecting grid neutral point directly to the PV negative terminal, thereby bypassing the PV stray capacitance.
It provides a low-cost solution consisting of only four power switches, two capacitors, and a single filter inductor. The proposed inverter is analyzed in detail and its switching pattern to generate multilevel output while maintaining the capacitor voltage is discussed.
Simulations and experiments results confirm the feasibility and good performance of the proposed inverter.
In this paper, a switching loss-free SLF concept for the first six-switches H-bridge inverter H6-I topology is proposed.Solar Ieee - Download as Word Doc .doc), PDF File .pdf), Text File .txt) or read online.
Working of PV cell: Working of a PV cell is based on the basic principle of photoelectric effect. and secondary energy from photosynthetic process that is mostly connected with the use of biomass and bio fuels.
Solar energy can be used by man in. Sensor Based Projects on Contactless liquid Level Control, Remote Cordless Mouse, Speed Checker, Ultrasonic Distance, Density Based Traffic signal etc. SCIENTIFIC PUBLICATIONS "Maximal Spontaneous Photon Emission and Energy Loss from Free Electrons" () Yi Yang, Aviram Massuda, Charles Roques-Carmes, Steven E.
Kooi, Thomas Christensen, Steven G. Johnson, John D. Joannopoulos, Owen D. Miller, Ido Kaminer & Marin Soljacic. Nature Physics, DOI: /s (). "Nanophotonic particle simulation and inverse . Installation and operation of apparatus, equipment, structures, materials and systems for the safe, reliable and economic generation, transmission, distribution, conversion, measurement and control of electric energy.
A free online environment where users can create, edit, and share electrical schematics, or convert between popular file formats like Eagle, Altium, and OrCAD. This paper investigates the possibility of charging battery electric vehicles at workplace in Netherlands using solar energy.
Data from the Dutch Meteorological Institute is used to determine the optimal orientation of PV panels for maximum energy yield in the Netherlands.